Absolute Optical Encoder: Kit Version Page 1 of 7 ► Installs onto shafts up to 10mm dia. ► 12-bit resolution, and resolution field programmable from 2 to 4096 codes per revolution (3600 factory default) ► Full 360 degrees range, 7 msec update time ► Low power drain of 18.5 mA max., and 2.5 mA in sleep mode ► Field programmable parameters such as setting zero position point (free demo software provided) ► EEPROM stores downloadable parameters ► 9600 baud default data rate adjustable up to 115K baud ► 12-bit analog voltage output option (0 to +3.599 volts factory default setting. Field programmable up to 0 to +4.095 volts) ► Multi-turn mode (note: power must be maintained to prevent reset to zero) ► -25 to 70 degrees C. operating temperature Description The A2K optical encoder is a 12 bit absolute rotary kit style encoder which reports a shaft angle within a single 360 degree rotation of a shaft. The kit style A2K allows the encoder to be easily assembled onto an existing shaft and bearing assembly. Unlike incremental, sometimes called relative, style encoders the A2K provides true (absolute) shaft position eliminating the need for a home or zero cycle after a supply voltage power cycle. The A2K communicates over a RS 485 style serial bus utilizing US Digital's SEI (Serial Encoder Interface) which allows for simple, quick and convenient networking of multiple SEI devices on a single network. PLCs, motion controllers and computers can also reside on the SEI bus as well by use of US Digital's SEI to USB interface device. For complete information about the SEI bus please refer to the SEI Communications Protocol webpage. The A2K is also available with an optional analog output. The analog output option provides a maximum voltage range of 0 to 4.095 volts with 12 bit resolution. The output voltage can be scaled by simple SEI commands to provide user defined voltage ranges. From the factory the analog output voltage is set to 0 to 3.599 VDC range. Please note that with the A2K analog output option only one device may reside on a SEI bus. DIGITAL Vancouver, Washington 98684, USA www.usdigital.com Toll-free: 800.736.0194

Absolute Optical Encoder: Kit Version Page 2 of 7 Mechanical Drawing ^ Environmental Parameter Operating Temperature Vibration (5Hz to 2kHz) Electrostatic Discharge,iEC 61000-4-2 Units C G kV 0 Mechanical Parameter Max. Shaft Axial Play Max. Shaft Total Indicated Runout Max. Acceleration Weight Moment of Inertia Max. Shaft Length Technical Bulletin TB1001 - Shaft and Bore Tolerances uss= DIGITAL 1400 NE 136th Avenue Vancouver, Washington 98684, USA [email protected] www.usdigital.com

Absolute Optical Encoder: Kit Version Page 3 of 7 Electrical ► Specifications apply over entire operating temperature range. ► Typical values are specified at Vcc = 12V and 25C. Parameter Min. Typ. Supply Current @ 12V supply Active 14 Analog Output Impedance 51 Zero Scale Analog Voltage 0 2 Full Scale Analog Voltage 4.066 4.095 Output Noise (Analog version) 10 Differential Nonlinearity (Analog version) -1.0 Integral Nonlinearity (Analog version) -1.0 Absolute Accuracy (SEI interface version) 0.18 Angle tracking speed Single-turn mode Multi-turn mode Position...

Absolute Optical Encoder: Kit Version Page 4 of 7 ^ SEI Network iQ; Analog Output The analog version of the A2K has a 12-bit DAC on the output which feeds to 2 lines that are otherwise used for the BUSY handshaking pair. This DAC has a full range of 0 to 4.095 Volts which is 1 mV per bit. The absolute position value which the internal microcontroller sends to that DAC is the same as the digital value that it sends to the host over SEI. Since the resolution (which represents the number of codes per revolution) is field programmable, the range of the DAC will also follow that setup. The default resolution...

Absolute Optical Encoder: Kit Version Page 5 of 7 Included Accessories Each A2K is shipped with all encoder components, centering tool, hex wrench, and two #4-40 x 1" cover screws. The following part numbers are provided if spares are needed. 1. Centering Tool Part #: CTOOL - (Shaft Diameter) Description: This reusable tool provides a simple method for accurately centering theA2K base onto the shaft. Instructions: When mounting encoder base, slide centering tool down shaft until it slips into centering hole of encoder base. Tighten mounting screws, then remove centering tool. 2. Hex Tool Part...

US5= A OLC Absolute Optical Encoder: Kit Version DIGITAL M^r\ Page 6 of 7 0 Assembly Instructions Assembly instructions for the A2K were affected by Product Change Notification PCN-4537-A2-HD25A, released on 8/18/2014. Please select the appropriate assembly instructions from the options below. For more information, download PCN-4537-A2-HD25A. A2K Assembly Instructions (affected by PCN-4537-A2-HD25A) Download the A2K Assembly Instructions A2K Assembly Instructions (not affected by PCN-4537-A2-HD25A) 1. Base Mounting Secure base by inserting screws through holes on the 1.812" bolt circle. Holes...

Absolute Optical Encoder: Kit Version Page 7 of 7 4. Cover Installation Important: Cover must be oriented as shown. Because cover plugs into the base, use caution during installation. The posts on the base are two different lengths. Match the cover to mate with the proper post. Connector pins can be damaged if not lined up properly. Secure with two 4-40 X 1" pan head screws provided. S =Default - SEI Bus 079 =2mm D =Default ► Cables and connectors are not included and must be ordered separately. ► US Digital® warrants its products against d efects in materials and workmanship for two years....